-LRB- CNN -RRB- -- President Obama authorized the killing of an American citizen because he had declared war on the United States and encouraged others to bring harm to America . Whatever Anwar al-Awlaki 's wrongs -- and there were many -- when America kills its own without a trial , it not only demeans itself but it hands over a propaganda victory to its enemies .

Ayman al-Zawahiri , al Qaeda 's leader since the death of Osama bin Laden , will chide this great country again for abandoning its values and principles . The White House 's authorization of this killing also tells American Muslims that a precedent has been set by their government to kill American citizens abroad without trial if they oppose their country .

This can not be right -- and is counterproductive to defeating terrorism in the long term because it demolishes the very values that America stands for : the rule of law and trial by jury .

It is abandoning these very same principles of human dignity , underpinned by free and fair trials that led to al-Awlaki 's decisive shift after being released from a Yemeni prison in 2007 : From being anti-American rabble-rouser , he went to advocating direct violence against the United States . Prison experiences in the Arab world -- being arrested and detained without legal representation and exposed to the worst forms of torture at the hands of fellow Muslims -- change nonviolent extremists to violent extremists . Al-Awlaki 's transformation from extremism to violence comes in this context .

His alleged links to 9/11 terrorists were not as significant as some argue . If he was known to be involved in the 9/11 attacks , why was he a guest of the Pentagon , of all places , in 2002 ?

Al-Awlaki is not alone . Before him , al-Zawahiri was tortured in Egyptian prisons , and during his trial in 1982 , he addressed a gallery of Western journalists in English and declared , `` So where is democracy ? Where is freedom ? Where is human rights ? Where is justice ? We will never forget ! ''

Without a doubt , al-Awlaki and al-Zawahiri were already radicalized before prison , but the tipping point toward violence came with their prison experiences . And before al-Zawahiri , the intellectual framework for al-Qaeda 's destructive worldview was put in place by Syed Qutb in Mazra Tora in prison in Nasser 's Egypt . Again , it was torture and the absence of humane treatment that led to Qutb declaring war on the Egyptian government . Qutb 's prison writings have inspired every jihadist movement around the globe .

This same movement sees al-Awlaki as a lightweight , not least because he never set foot on the battlefield and his scholarly credentials are open to question . In Egypt or Pakistan , al-Awlaki is not well-known . Little wonder , then , that Al Jazeera Arabic is not as excited by al-Awlaki 's killing as Western media outlets .

Al-Awlaki was important among Muslims in the West -- from Yemen , he used the Internet to reach this constituency . But even before the launch of his blog in 2008 , al-Awlaki was popular among Muslims in England , Canada and America because of his audiotapes about the history of early Muslim personalities . These tapes were , and many still are , in circulation in mosques and bookshops .

Al-Awlaki could have been discredited before his prison experiences or , now , his perceived martyrdom . By killing al-Awlaki , his message gains new life as words from an American Muslim martyr , the first to join the iconography of underground Muslim culture since Malcolm X .

An easier , cheaper and more effective way of discrediting al-Awlaki and countering his message would have been to disclose his three arrests for the solicitation of prostitutes in San Diego and the Washington , D.C. , area between 1996 and 1997 . He had even pleaded guilty to the 1997 charge , and was subsequently sentenced to three years ' probation and a fine . Among his socially conservative Muslim following in Europe and America , immediately after 9/11 , such information would have been dynamite .

The United States can not kill its way out of terrorism . Just as with the Cold War , the challenge from Islamist extremism and jihadist violence urgently needs a cultural , intellectual and informational response . Violence breeds more violence and , in this case , literally creates martyrs out of al Qaeda 's murderers .

The opinions expressed in this commentary are solely those of Ed Husain .

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Ed Husain : Killing Anwar al-Awlaki demolishes the values that America stands for

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The killing also gives a propaganda victory to America 's enemies , he says

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Husain : Al-Awlaki could have been discredited before he radicalized

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The United States can not kill its way out of terrorism , Husain says